Apparatus for mixing fluid masses



Sept. 8, 1936. G. M. PFAU ET AL 2,053,876

APPARATUS FOR MIXING FLUID MASSES Original Filed Aug. 9, 1932 M iWIIIIIIIII/I? Patented Sept. 8, 1936 I UNITED STATES PATENT OFFICEAPPARATUS FOR MIXING FLUID MASSES corporation of Texas Originalapplication August 9, 1932, Serial No. 628,064. Divided and thisapplication May 17, 1933, Serial No. 671,428

' 3 Claims. (01. 259-9) This invention relates to an apparatus for theagitation or intimate mixing of liquid or semiliquid masses of two ormore materials and more particularly relates to an apparatus which willbring about a shearing action on the respective substances as they passthrough the device. This application is a division of our copendingapplication Serial No. 628,064, filed August 9, 1932.

An object of the present invention is to provide an apparatus capable ofeffecting extremely intimate contact between two or more liquids inminimum periods of time.

Another of the objects of this invention is to provide a multiple seriesform of agitator having a plurality of separate compartments adapted toprogressively receive and intimately mix two or more semi-fluid or fluidsubstances and to squeeze the substances during passage from onecompartment to another in such manner that a shearing action iseifected, thereby accomplishing a mixing in which even the smallestparticles or portions of the diverse materials are contacted and inwhich clots of untreated material are prevented from forming.

Another object of our invention is to provide a multiple series agitatorcomprising a number of separate compartments of substantially identicalconstruction so designed that one or more compartments may be added toor taken away from the complete unit to either increase or decrease theamount of agitation applied to the material passed therethrough.

Another object of the invention is to provide a multiple series agitatorincluding a plurality of separate compartments each of which con-' tainsa rotatable paddle constructed in such form that when rotated itprogressively forces the substances entering at one end, through thecompartment and out at the other end while maintaining a constantrotation and intermixing action.

Another object of the invention is to provide in the multiple-stepagitator one or a series of shearing units each cons'isting of a bafliehaving Further objects and advantages of our invention will appear fromthe following description thereof taken in connection with the attacheddrawing which illustrates the preferred embodiment of the apparatus.

In many industries the mixing of liquids and semi-liquid masses requiresa very intimate admixture of the respective materials not only to makethe contact as complete as possible, but also to prevent the formationof clots of untreated material. We have found that the paddles, airblasts and other devices heretofore used to bring treating agents intocontact with materials are in many cases very inefiicient, and oftenmake necessary the use of large quantities of treating material farbeyondthe amount theoretically required. In the present apparatus wehave provided for such thorough and intimate mixing of liquids andsemi-liquid masses that thequantity of treating liquid or agent may bereduced by a surprisingly large percentage.

In the drawing:

Figure 1 is a side elevation of a multiple series agitator with partsbroken away and other parts in section to show the internalconstruction;

Figure 2 is a transverse section taken substantially on the line 2-2 ofFigure 1, showing the rotatable disk;

Figure 3 is a transverse section taken particularly on the line 3-3 ofFigure 1 showing the fixed baille;

Figure 4 is an end elevation of the paddle.

The multiple agitator as shown in Figure 1 is composed of a plurality ofseparate chambers or units I2, l4 and I6. The intermediate units M arethe same in size and shape. All of the units are standardized as toflanges or other fittings so that they may be bolted together to form acomplete agitator. The end units l2 and iii are similar in size andconstruction to the intermediate units and difier only in that the inletend section I2 is provided with intake conduits 20 and 22 and has norotatable disk, and the outlet end section -Hi is provided with adischarge conduit 24 and has no baflie plate. It is not essential tohave two intake conduits, for the materials to be mixed may be broughttogether at an outside point and introduced into the agitator in asingle intake conduit. Additional inlet and outlet conduits if desiredfor any special purpose may be provided and connected directly to any ofthe compartments, to the end or the intermediate sections.

The multiple agitator, preferably cylindrical in form, has itscompartments or units separated by stationary baifie plates'ZS, as shownin Figures 1 and 3. Each baiiie plate preferably has a plurality ofholes 21 through which the liquid mass is forced. Mounted on the shaft32 immediately adjacent each baiile plate there is a rotatable disk 28having several vane type slots or grooves 29 which extend from nearthecenter to a point at the periphery of the disk which grooves serve asconduits for the mixture passing through the baifie and assist inobtaining the shearing action on the mixture by the rubbing contactbetween the fixed baille plate and the rotatable disk. The clearancebetween the disk and the baiile is pref.- erably small, and while itwill vary with different products it should be not more than one-eighthinch for most liquid mixtures for good results. A

clearance as little as one-sixty-fourth inch gives best results in manycases.

Each compartment or tank also has a rotatable paddle means having ,ablade support 30 mounted on the central driving shaft 32 which in turnmay be conveniently rotated by the pulley 34 mounted on an outer endthereof. Suitable packing boxes 35 are used on the ends of the agitatorto seal the compartments against leakage at the shafting.

The rotatable paddlepreferably has two blades 3i and 33 which may be ofa curved or ribbon type. Withreference to Figure 1 the interior of thecompartment I6 is illustrated, the casing being merely broken away thusshowing the whole paddle means including both ends of the blades.

The adjacent compartment M is illustrated as a I central section throughthe blade support and thus shows the blades 3! and 33 broken at thecenter line. The arrangement of the shaft, the blade support and theblades is more clearly shown in Figure 4.

The blades 3i and 38 extend substantially the whole length of thecompartments leaving a small .clearance from the interior end and sidesurfaces thereof. Because of this arrangement of parts, the paddleexertsa conveying or pumping action on the liquid introduced therein, thusagitat ing the liquid mass and simultaneously pumping the same throughand out of the compartment through the holes in the baffle into thespace between the disk and the baiile wherein a shearing action isobtained.

The operation of the device is substantially as follows:

The liquid or semi-plastic mass to be treated may be introduced into thefirst compartment to- 'gether with the treating liquid through one inletconduit or the treatingliquid may be introduced through a separateconduit. In this compart- ,ment the paddle rotates throughout the mass,in-

timately mixing and stirring the products together. Due to the pumpingaction of the paddle,

the mass is continuously pumped through the due to its rotation andclose relationship to the baiiie causes the mixture to travel to theperiphery.

compartment, through the apertures relatively near the center of thecompartment. As the mixture discharges from the apertures, it comes intoimmediate contact with the shearing disk which,

to be discharged into the second compartment wherein it is againintimately mixed, and again is pumped to the next baille. In each unitthe liquid starts at theperiphery of the chamber and in passingtherethrough is forced substantially to the center to pass through theapertures in the bailie after whichit is squeezed outwardly to tained.

v. The outward movement along the face of the baflle is accompanied by ashearing action on the liquids aided by the vanes which conduct some ofthe mixture from the apertures, the whole mixture moving radially in anoutward direction and at the same time moving spirally as a result ofthe disk.

Because of the novel construction of the instant apparatus, the materialto be treated and the treating agent are continuously forcedtherethrough during continuous agitation. The probability that any'ofthe materials being treated escapes without a very intimate contact withthe treating agent is at a minimum. This intimate mixing in combinationwith forced feeding prevents the overtreatment of any part of thematerial as well as the undertreatment of any part.

Although the apparatus is general in application, it is particularlyadapted for the intimate mixing of sulphuric acid and heavy lubricatingoils. In such a process the agitator is preferably constructed of acorrosion resisting metal to prevent damage by the acids. It is ofcourse apparent that other treating agents may be agitated in theinstant apparatus with any other material of sufliciently fluid qualitythat can be pumped through the agitator. It is also obvious that thetreating agent can be added to more than one unit if sequentialaddition-is desirable. It is also obvious that the size as well asnumber of the units will depend on the materials to be treated and thetreating agent. If necessary or desirable within the terms of the claimsappended hereinafter.

We claim: 1. agitating apparatus of the class described for intimatelymixing substances forming a pump able liquid mass which comprises, aplurality of communicatively connected mixing compartments, inlet andoutlet means for said compar ments, bai'iie members between each of thecompartments for restricting the free flow of mass, 9. driving shaft,rotatable paddles carried by the shaft, said paddles .being adapted toforce'the mass past the baiiles from one compartment to another, anddisks closely adjacent the baffle members, said disks being adapted'tocause a shearing action and a greater surface contact between theliquids passing through the baflles.

2. An agitating apparatus for intimately mixing sulfuric acid andlubricating oil without emulsifying the same comprising a plurality ofagitating tanks of similar construction detachably arranged in seriesmeans for introducing sulfuric acid and heavy lubricating oil into thefirst tank in the series, a shaft extending through said tankscoextensively therewith, a rotatable impeller paddle mounted on saidshaft in each tank, said paddles being adapted to agitate the mixtureof-liquids in their respective tanks and impel the same progressivelyfrom tank to tank, a

' stationary plate between each tank through which said shaft extends,said. plates being provided with comparatively small perforationsadjacent their centers and being imperforate adjacent their peripheriesthus providing throttling means i for retarding the flow of liquidsbetween the tanks increase the area of contact between the oil andsulfuric acid, means to rotate said shaft at a constant speed to causesaid paddles to impel the liquids through said tanks at a constantspeed, and an outlet for the intimately mixed liquids in the last tankinthe series.

3. An agitating apparatus for intimately mixing sulfuric acid andlubricating oil without emulsifying the same comprising a plurality oiagitating tanks arranged in series, means for introducing sulfuric acidand lubricating oil into the first tank in the series, a shaft extendingthrough said tanks coextensively therewith, a rotatable impeller'paddlemounted on said shaft in each tank, said paddles being adapted toagitate the mixture of liquids in their respective tanks and impel thesame progressively from tank to tank, a stationary plate between eachtank through which said shaft extends, said plates being provided withcomparatively small localized perforations thus providing throttlingmeans for retarding the flowof liquids between the tanks and providingbaffle means for causing the liquid toconverge in passing from one tankto another, a disk mounted on said shaft adjacent each plate and adaptedto rotate therewith, said plates and disks presenting opposed minutelyseparated smearing surfaces, the smearing surfaces on said disks beingprovided with grooves overlying the perforations on said plates wherebythe liquids in passing from one tank to another will pass through saidperforations and be smeared through said smearing surfaces to increasethe contact between the oil and sulfuric acid, and means to rotate saidshaft, and an outlet for the intimately mixed liquids in the last tankin the series.

GEORGE M. PFAU. DAYTON C. BOLIN. ERNESTW. ZU'BLIN..

